biofuels

MIT researchers engineer cells for more efficient biofuel production

Researchers at the Massachusetts Institute of Technology in the US have devised a way to dramatically boost the production of isobutanol -- a heavy alcohol -- in yeast, giving hope to those engaged in the long search to discover an alternative, not just to fossil fuels, but to ethanol as well.

Not only do heavy alcohols such as isobutanol contain more energy than ethanol, but they are also more compatible with existing gasoline-based infrastructure.

But according to Gregory Stephanopoulos, an MIT professor of chemical engineering and one of the senior authors of a paper describing the work in the Feb. 17 online edition of Nature Biotechnology, for isobutanol to become practical, scientists need a way to reliably produce it in great quantities from renewable sources.

In the MIT experiments, the isobutanol synthesis takes place entirely within mitochondria, cell structures that generate energy and also host many biosynthetic pathways. In its paper, the team said it boosted isobutanol production by about 260 percent.

Stephanopoulos told Phys.org that while the amount of isobutanol was still not at a scale to make it a practical challenger to ethanol. the research is nonetheless, "opening up the opportunity to make a lot of biochemicals inside an organelle that may be much better suited for this purpose compared to the cytosol of the yeast cells."

Stephanopoulos collaborated with Gerald Fink, an MIT professor of biology and member of the Whitehead Institute, on this research. The lead author of the paper is Jose Avalos, a post doctoral researcher at the Whitehead Institute and MIT.

Historically, researchers have tried to decrease isobutanol production in yeast, because it can ruin the flavor of wine and beer.

But Avalos told Phys.org the game has changed as people realized its potential as a fuel and in other chemical applications.